Compostos fenólicos da casca de Handroanthus heptaphyllus (Mart. ) Mattos e efeitos do extrato aquoso no perfil lipídico, glicêmico e na lipoperoxidação em ratos diabéticos / Phenolic compounds from Handroanthus heptaphyllus (Mart. ) Mattos bark and effects of aqueous extract on lipid profile, glucose, and lipid peroxidation in diabetic rats

RESUMO A preocupação com o tratamento do Diabetes mellitus (DM) leva a uma crescente busca por terapias alternativas, como o uso de plantas medicinais, entre as quais, destaca-se o uso de Handroanthus heptaphyllus (Mart.) Mattos (popular Ipê roxo). Neste estudo realizamos a investigação química da presença de compostos fenólicos em H. heptaphyllus e o efeito do tratamento com o extrato aquoso da casca desta planta em parâmetros bioquímicos e nos níveis de lipoperoxidação tecidual e plasmática em animais diabéticos. Metodologia: Ratos Wistar machos foram submetidos ao desenvolvimento do quadro de DM por meio da administração intraperitoneal (IP) de Aloxano monohidrato (150 mg/Kg IP). Após a confirmação de hiperglicemia (>200 mg dL-1), os animais foram distribuídos nos grupos Diabético (D; n=6) e Diabético Tratado (DT; n=6). O tratamento consistiu na administração diária do extrato aquoso da casca de H. heptaphyllus via oral (v.o.) (150mg/Kg v.o.) por quatro semanas. O extrato aquoso foi analisado qualitativamente por cromatografia de camada delgada. Resultados: A análise qualitativa do extrato aquoso da casca indicou a presença de compostos fenólicos da subclasse flavonoides. O tratamento com o extrato aquoso reduziu a glicemia de jejum a partir da 3ª semana de tratamento, melhorou a resposta glicêmica à sobrecarga de glicose, diminuiu os níveis de triglicerídeos e índice LDL (Triglicerídeos/HDL). Estes resultados sugerem o uso terapêutico do extrato aquoso das cascas de H. heptaphyllus no tratamento do DM.

ABSTRACT Alternative medicine for diabetes mellitus (DM) treatment represents a growing research area on the use of medicinal plants, of which Handroanthus heptaphyllus (mart.) Mattos (popularly known as purple ipe) is most prominent. In this study, we investigated the presence of phenolic compounds and the effects of treatment with aqueous extract of in H. heptaphyllus in biochemical profile in plasma and the levels of lipid peroxidation in tissues and plasma in diabetic animals. Male Wistar rats were induced to develop DM through intraperitoneal (IP) administration of alloxan monohydrate (150 mg/kg IP). Once hyperglycemia (>200 mg dL-1) was confirmed, the animals were divided into the Diabetic (D; n=6) and Treated Diabetic (TD; n=6) groups. The TD group received daily administration (150 mg/kg v.o.) of aqueous extract of H. heptaphyllus for four weeks. The aqueous extract was also analyzed qualitatively by layer chromatography. Qualitative analysis of the aqueous extract of the bark indicated the presence of phenolic compounds from the flavonoid subclass. The treatment with the aqueous extract reduced fasting blood glucose levels from the third week of treatment on, improved the glycemic response to the glucose tolerance test, and lowered the levels of triglycerides and the LDL index (triglycerides/HDL). These findings suggest therapeutic use of the aqueous extract of H. heptaphyllus bark in treating DM.

Gallopamil activity on asynergic viable myocardium in acute myocardial infarction: insights on stunned and hibernating myocardium.

The influence of the calcium antagonist gallopamil on the contractility of asynergic viable myocardium after acute myocardial infarction treated with thrombolysis was investigated by two-dimensional echocardiography. Sixteen patients with > or = 1 viable segment(s), identified during the low-dose phase (up to 10 micrograms/kg/min) of a dobutamine echocardiographic test (up to 40 micrograms/kg/min) performed 4-5 days after a first acute myocardial infarction, were given a gallopamil intravenous bolus (50 micrograms/kg) 12-24 hours later. Two-dimensional echocardiography was done before and 15 minutes after the bolus. A score index of 1 (normokinesis) to 4 (dyskinesis) and a 16-segment model were used. A segment was considered viable when a resting asynergy (score > or = 2) improvement of > or = 1 grade was seen during low-dose dobutamine. Follow-up echocardiograms were done 3-5 months later. A total of 30 viable segments were found; of these, 10 showed sustained improvement in contractility (group A) during high-dose dobutamine, while 20 exhibited a biphasic response returning to their basal contractile state (group B). After the gallopamil bolus, 9 of 10 group A segments improved their contractility, in comparison with 0 of 20 group B segments (P < .001). Infarct-related vessel significant (> or = 75%) coronary stenosis was present in the tributary vessel of 0 of 10 group A and of 20 of 20 group B segments (P < .001). At follow-up, 9 of 10 group A segments showed a spontaneous contractile improvement; of the 20 group B segments, 8 of 10 that underwent revascularization (7 angioplasty, 3 bypass graft) showed contractile improvement, in comparison with 0 of 10 segments not revascularized (P = .001). We conclude that gallopamil may reverse the contractile dysfunction of postischemic stunned myocardium in patients with acute myocardial infarction, whereas no effects are apparent on ischemic/hibernating myocardium.

[Early echocardiographic identification of viable myocardium after acute myocardial infarct using inotropic agents: comparison of dobutamine and enoximone]. / Ricerca ecocardiografica precoce del miocardio vitale dopo infarto miocardico acuto con agenti inotropi: confronto tra dobutamina ed enoximone.

BACKGROUND: The reversibility of regional dysfunction early after acute myocardial infarction may be obtained with inotropic adrenergic stimulation, in particular during low dose dobutamine infusion, suggesting the presence of viable myocardium. The aim of this study was to determine whether viable myocardium can be identified by two-dimensional echocardiography after an i.v. bolus of enoximone-positive inotropic non-adrenergic drug, phosphodiesterase III inhibitor as well as during dobutamine infusion, in patients with acute myocardial infarction. METHODS: Twelve male patients, aged 57 +/- 10 years and treated with rtPA (100 mg i.v. in 180 minutes) within the first 6 hours of a first anterior myocardial infarction were studied. All patients underwent a dobutamine infusion (5 and 10 mcg/kg/min, 5 minutes per dose) 4 +/- 1 days after entrance, followed by an enoximone bolus (1 mg/kg over 5 minutes) 1 hour later. Echocardiography was performed before dobutamine and enoximone, during dobutamine, 10 minutes after enoximone and at 6 +/- 2 months follow-up. A Wall Motion Score Index (WMSI) was calculated as recommended by the American Society of Echocardiography. All patients underwent coronarography on days 9-11 post-infarction. RESULTS: Improvement in regional function of basally asynergic segments occurred in 8 patients during dobutamine infusion, as well as after enoximone i.v. bolus, and in 1 patient only during dobutamine infusion. Both dobutamine and enoximone tests were found to be negative in the other 3 patients. A decrease of WMSI was observed with both dobutamine and enoximone tests (from 1.84 +/- 0.32 to 1.73 +/- 0.31; p = .002 with dobutamine; from 1.84 +/- 0.32 to 1.70 +/- 0.27; p = .0132 with enoximone) with concordant wall motion changes between two tests in 73/84 (87%; K = 0.61) basally asynergic segments. There were no complications occurred during the study. Of 8 patients with positive response for viable myocardium to both tests, 6 had a patent and 2 an occluded infarct-related artery. However, in the latter a collateral circulation toward necrotic area was present. At follow-up improvement in regional function of basally asynergic segments, with a decrease of WMSI (from 1.74 +/- 0.23 to 1.59 +/- 0.24; p < .05), was observed in 4 of 8 patients with viable myocardium detected by either dobutamine or enoximone. CONCLUSIONS: 1) Viable asynergic myocardium may be identified early after acute myocardial infarction by enoximone bolus, as carefully and safely as by dobutamine infusion; 2) transient recovery of post-ischemic myocardial dysfunction may be obtained independently of beta-receptor stimulation.

Peak exercise left ventricular performance in normal subjects and in athletes assessed by first-pass radionuclide angiography.

The role of Frank-Starling law of the heart in determining the increase in cardiac output during exercise in humans is still controversial (e.g., the mechanisms responsible for the enhancement of left ventricular [LV] filling during the shortened diastolic interval). Ten weight lifters, 12 swimmers and 12 sedentary subjects who underwent maximal upright bicycle exercise testing were studied. First-pass radionuclide angiography was performed both at rest and at peak exercise using a multicrystal gamma camera. Compared with resting values, heart rate and cardiac index at peak exercise increased by 101 +/- 16 beats/min (p less than 0.001) and 6.7 +/- 2.8 liters/min/m2 (p less than 0.001) in weight lifters, by 96 +/- 9 beats/min (p less than 0.001) and 9.5 +/- 2 liters/min/m2 (p less than 0.001) in swimmers, and by 103 +/- 9 beats/min (p less than 0.001) and 7.3 +/- 1.8 liters/min/m2 (p less than 0.001) in sedentary subjects. Stroke volume increased by 20.5 +/- 9.8 ml/m2 (p less than 0.001) in swimmers only. End-diastolic volume at peak exercise did not change in weight lifters and in swimmers; it decreased by 8.2 +/- 8.6 ml/m2 (p less than 0.01) in sedentary subjects. A significant correlation was found between the decrease in end-systolic volume and the increase in peak rapid filling rate at peak exercise in all 3 groups (r = 0.65, p less than 0.05 in weight lifters; r = 0.59, p less than 0.05 in swimmers; r = 0.67, p less than 0.05 in sedentary subjects.(ABSTRACT TRUNCATED AT 250 WORDS)